Pulley



I June 14, 1938. C(WATSON PULLEY 2 Sheets-Sheet 1 Filed Sept. 4, 1936June 14, 1938. H. c. WATSON PULLEY Filed Sept. '4, 1936 2 Shpets-Sheet 2M INVENTOR.

. v w\ k f w k. k kh Patented June 14, 1938 PATENT OFFICE PULLEY HarryC. Watson, Chicago, 111., assignor to American Electric FusionCorporation, Chicago, 111., a corporation of Illinois ApplicationSeptember 4, 1936, Serial No. 99,413

Claims.

This invention relates to a novel and improved form of pulley, the novelfeatures of which will be best understood from the following descriptionand the annexed drawings, in which I 5 have shown a selected embodimentof the invention and in which:

Fig. 1 is a longitudinal section through a shaft having a pulley appliedthereto;

Fig. 2 is a section approximately on the line 22 of Fig. 1;

Fig. 3 is a view corresponding to Fig. 1 but showing the parts indifferent positions;

Fig. 4 is a section approximately on the line 4-4 of Fig. 3; Fig. 5 is aperspective view of one of the keys appearing in the other figures;

Fig. 6 is a section approximately on the line v 6-6 of Fig. 1.

The invention is shown as being used in connection with a shaft I whichmay be secured to a motor shaft 2, as in the copending application ofEdmund J. von Henke, Ser. No. 99,219, filed September 3, 1936. The twoshafts I and 2 are keyed together at 3 so that they are in effect oneshaft.

The shaft I is shown as being provided with two diametrically opposedkeyways l in which slide keys 5, the construction of which will probablybe best understood from Fig. 5. Each one so of these keys may slidefreely lengthwise of the shaft, but rotates therewith and is providedwith a circumferentially extending key 6 adapted to be received in acircumferential groove 1 in the hub 8 of one flange 9 of the pulley,whereby the flange 9 will move with the key 5 lengthwise of the shaft.

Cooperating with the flange 9 is a separate flange III which togetherform the pulley, and both flanges 9 and II] are keyed to the shaft to 40rotate therewith by means of the keys 5, as plainly shown in Figs. 2 and4. The two flanges are provided with recesses, forming between themoverlapping teeth II and I2, each of which is adapted to enter a recesson the other flange.

These teeth also may be used, if desired, to cause the two flangesto'rotate together, although ordinarily the keyed connections to theshaft described above will be sufiicient and therefore I have shown inthe drawings that the teeth I I and I2 are not in engagement.

(Cl. 74-23mm oted between its ends. The pivot I5 for each lever is shownas being on an ear I6, and one end of the lever contacts with a bearingI! on the flange I0, while the other end bears against one end of thekey 5.

The two flanges are normally urged together by means of a compressionspring I8, and therefore a belt I9 which may run over the pulley will bedriven thereby or may drive the pulley, as the case may be, and mayoccupy some such position as shown in Figs. 1 and 2. Assuming, however,that for any reason at all the tension on the belt increases, then thetwo flanges 9 and II) will be moved in opposite directions away fromeach other. The two lever ams of. each lever I4 are equal so that, asthe flange III moves towards the right, that movement will impart anequal movement in the opposite direction to the keys 5,

, which in turn will force the flange '9 to the left against the actionof the spring I8. If, for any reason, the tension on the belt increases,then these movements will be reversed so that the two flanges will bemoved towards each other by equal amounts.

By the above arrangement, it will be seen that the belt I9 is alwaysmaintained in the same position lengthwise of the shaft. This isimportant where, for example, the pulley is used to drive ment of thebelt lengthwise of the shaft would not be accompanied by a likedisplacement of the While I have shown the invention as embodied in aspecific form, it is to be understood that various changes in detailsmay be made without departing from the scope of the invention, asdeflned by the appended claims.

IcIaim:

1. In combinatiomfla shaft having a key movable lengthwise thereof, apulley on said shaft and formed of two separate flanges, means causingsaid flanges to rotate together, one of said flanges being movable withsaid key and the second movable with respect to the key lengthwise ofthe shaft, and means actuated by movement of said second flangelengthwise of the shaft, to cause movement of the key and thefirst-named flange in the opposite direction.

' 2. In combination, a shaft, a pulley on said some piece of machineryand where a displace-,-

shaft and formed of two separate flanges, a key slidable lengthwise ofsaid shaft, a circumferential key connecting said slidable key and oneofsaid flanges, a lever engaged by the second flange and adapted, uponmovement of said second flange away from the first-named flange, to movesaid slidable key and said first-named flange an equal amount in theopposite direction, and means flange, to move said slidable key and saidflrst-' named flange an equal amount in the opposite direction, andmeans yieldingly resisting said movements.

4. In combination, a shaft, a pulley on said shaft and formed of twoseparate flanges, a key slidable lengthwise of said shaft but rotatabletherewith, a circumferential key connecting said slidable key and one ofsaid flanges, a lever enaged by the second flange and adapted, uponmovement of said second flange away from the first-named flange, to movesaid slidable key and said first-named flange an equal amount in theopposite direction, a spring'resisting said movements, and means causingsaid flanges to rotate in unison with each other.

5. In combination, a shaft, a pulley on said shaft and comprising twoseparate flanges each keyed to the shaft to rotate therewith but movableaxially thereof, means yieldingly urging said flanges towards eachother, a collar secured to said shaft adjacent one of said flanges, alever

